1. Field of the Invention
The present invention relates to a cutter for cutting a material such as paper by means of a shearing force.
2. Description of the Prior Art
Generally, a cutter for cutting a thin material such as photographic paper by means of a shearing force has a fixed blade and a movable blade which engages therewith. In an arrangement in which the movable blade engages with the fixed blade as the former reciprocates relative to the latter, it is necessary for the movable blade and the fixed blade to intersect each other in the shape of X as viewed along the moving plane of the movable blade. If the movable blade and the fixed blade are disposed simply in parallel, it is impossible to cut a thin material. For instance, in an ordinary pair of scissors, a pair of blades do not reciprocate linearly but rotate relative to each other. However, in this case as well, intersection in the X-shaped manner is maintained as in the case of the reciprocating cutter.
In order to engage the movable blade with the fixed blade in the X-shaped manner, it is necessary to install the movable blade on a movable base for reciprocating the same, and an urging means is required to generate a force for engaging the movable blade with the fixed blade. Generally, a structure is adopted in which the movable blade is made rotatable about an axis which is parallel to a cutting line, i.e., the line of the edge of the fixed blade, the movable blade is urged by a resilient member, and the edge of the movable blade is engaged with that of the fixed blade. In this case, however, since the fixed blade moves by a slight amount by means of this urging force, it is impossible to cut the material at accurate intervals.